Some prior art valvetrains are selectively adjustable to vary the amount of valve travel during opening. Typically, such valvetrains are selectively adjustable between a low-lift mode, in which the valvetrain causes an engine poppet valve to open a first predetermined amount (with lost motion), and a high-lift mode, in which the valvetrain causes the poppet valve to open a second predetermined amount that is greater than the first predetermined amount.
Lash adjusters are used to accommodate for build variations and wear in a valvetrain assembly. Known deactivating lash adjusters require significant length to achieve lost-motion, and can therefore be difficult to package.